Allow to configure local static zone files dir

[dheid]

Hi @doobry-systemli

This pull request enables the configuration of a local static zone files directory for enhanced customization and management within the systemli/ansible-role-bind9. This feature provides users with the flexibility to specify a dedicated directory for storing static zone files locally.

Changes:

• Modified defaults/main.yml:
  Added bind9_local_static_zone_filesdir variable to configure the directory path for local static zone files.
• Modified tasks/main.yml:
  Updated the source path for static bind9 zone files to use the newly introduced bind9_local_static_zone_filesdir variable, allowing dynamic customization of the directory path.

This enhancement streamlines the management of static zone files, empowering users to organize and maintain their configurations efficiently.

Best regards
Daniel